1. Field of the Invention
The present invention relates to a processing apparatus and an image forming system including the processing apparatus that executes a process of selectively heating different areas in a direction substantially orthogonal to a conveyance direction of a to-be-processed medium through a film.
2. Description of the Related Art
Conventionally, the gloss of the surface of most printed matter varies, depending on the coverage rate, because the glossiness of the recording material and the glossiness of color material are different. For such a printed matter, various methods are proposed to create a uniform glossy surface over the entire surface of the printed matter through various post-processes such as over-coating.
In recent years, a demand for a fully glossy image or a printed matter with a high added value of partial glossing is increasing in an electrophotographic system. Japanese Patent Application Laid-Open No. 2007-086747 proposes a method of improving the gloss of the entire surface of a printed matter and recording a photographic tone. In the method, the surface of the printed matter provided with an image by toners is reheated through an endless belt with a highly smooth surface to melt the toners again. The toners are then cooled while the toners are in touch with the belt, and the toners are solidified while the smoothness of the belt is transferred to the surface of the image formed by the toners. Although the gloss of the entire printed matter can be controlled in the method, the gloss of the surface of the printed matter cannot be partially controlled.
Meanwhile, Japanese Patent Application Laid-Open No. 2004-170548 discloses a method of using a thermal head to partially control the gloss of the surface of a printed matter. Specifically, a configuration is disclosed, in which the thermal head partially heats the surface of a sheet body, the sheet body is conveyed while a pressure roller presses the sheet body against an endless belt, and the sheet body is cooled while the sheet body is in close contact with the endless belt.
However, the sheet shrinks if the sheet is heated prior to a selective heating process of an arbitrary position. Therefore, if the shrinkage of the sheet is ignored to partially heat the sheet, there is a problem that the gloss of a section different from an intended section is changed.